High Speed USB 2.0 (480Mbps)
DPDT Analog Switch
SGM7227
APPLICATION INFORMATION
Power-Off Protection
Power-On Protection
When D+ or D- is shorted to VBUS, there is a special
protection circuit inside the SGM7227, so that the
device will not be damaged within 24 hours. In case of
power-down or over-voltage event, the protection
circuit can prevent the leakage signal on D+/D- pins to
ensure the reliability of the system.
The USB 2.0 specification requires USB device to
ensure that the device will not be damaged even if VBUS
short-circuit occurs during data transmission. Therefore,
under over-voltage conditions, the SGM7227 will limit
the current flowing back to the VCC track, and the
current will not exceed the safe operating range.
USB2.0 Signal Quality Compliance Test Results
The results of USB eye map test are shown in Figure 2 and Figure 3. The SGM7227 passes all the tests.
Required Tests
Overall result:
Pass!
Additional Information
Consecutive jitter range:
-61.770ps to 39.668ps, RMS jitter 21.900ps
Signal eye:
Paired JK jitter range:
Eye passes
-47.800ps to 42.890ps, RMS jitter 21.591ps
EOP width: 7.91 bits
Paired KJ jitter range:
EOP width passes
-50.590ps to 49.704ps, RMS jitter 23.281ps
Measured signaling rate: 480.0551MHz
Signal rate passes
Rising Edge Rate:
901.28V/μs (710.10ps equivalent rise-time)
Passes
Falling Edge Rate:
889.18V/μs (719.77ps equivalent rise-time)
Passes
Figure 1. Waveform Plot
Figure 2. High-Speed Signal Quality Eye Diagram Test
(VCC = 3.3V)
SG Micro Corp
www.sg-micro.com
MAY 2022
9
SGMICRO [ Shengbang Microelectronics Co, Ltd ]
